Age spots — also called liver spots and solar lentigines — are flat tan, brown or black spots. They vary in size and usually appear on the face, hands, shoulders and arms — areas most exposed to the sun.

Age spots are very common in adults older than age 50. But, younger people can get them too, especially if they spend a lot of time in the sun.

Although age spots can look like cancerous growths, true age spots are harmless and don't need treatment. For cosmetic reasons, age spots can be lightened with skin-bleaching products or removed. However, preventing age spots — by avoiding the sun and using sunscreen — may be the easiest way to maintain your skin's youthful appearance.

Age spots typically develop in people with a fair complexion, but they can be seen in those with darker skin. Age spots:

Are flat, oval areas of increased pigmentation

Are usually tan, brown or black

Occur on skin that has had the most sun exposure over the years, such as the backs of hands, tops of feet, face, shoulders and upper back

Age spots range from freckle size to more than 1/2 inch (13 millimeters) across and can group together, making them more prominent.

When to see a doctor

You may not like the way they look, but age spots are usually harmless and don't require medical care. However, your doctor should evaluate spots that are dark or have changed in appearance, because these changes can be signs of melanoma, a serious form of skin cancer.

It's best to have any new skin changes evaluated by a doctor, especially if a spot or lesion:

Is darkly pigmented

Is rapidly increasing in size

Has an irregular border

Has an unusual combination of colors

Is accompanied by itching, redness, tenderness or bleeding

Age spots are caused primarily by years of exposure to ultraviolet (UV) light from the sun. The use of commercial tanning lamps and tanning beds can also contribute to the development of age spots.

The pigment in the upper layer of skin (epidermis) that gives your skin its normal color is called melanin. UV light accelerates the production of melanin, creating a tan that helps protect deeper layers of skin from UV rays.

On areas of the skin that have years of frequent and prolonged sun exposure, age spots appear when melanin becomes "clumped" or is produced in particularly high concentrations.

Although anyone can develop age spots, you may be more likely to develop the condition if you:

Have light-colored or fair skin

Have a history of frequent or intense sun exposure or sunburn

You're likely to start by seeing your family doctor or primary care doctor. However, in some cases when you call to set up an appointment, you may be referred to a specialist in skin diseases (dermatologist).

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

When did you first notice the spots on your skin?

Did the spots appear gradually or quickly?

Have you noticed any other changes in the appearance of your skin?

Is the condition itchy, tender or otherwise bothersome?

Have you experienced frequent or severe sunburns?

How often are you exposed to sun or UV radiation?

Do you regularly protect your skin from UV radiation?

What kind of sun protection do you use?

Questions for your doctor

Questions you may want to ask your doctor include:

What suspicious changes in my skin should I look for?

If the spots are age spots, what can I do to improve the appearance?

Do treatments make them go away completely, or do they just lighten the age spots?

Skin biopsy. If there's any doubt whether something is an age spot or not, your doctor may do other tests, such as a skin biopsy. During a skin biopsy, your doctor takes a small sample of your skin (biopsy) for microscopic analysis. A skin biopsy is usually done in a doctor's office, using a local anesthetic.

Other conditions

Other conditions that can look similar to age spots and that your doctor may need to rule out include the following:

Moles. Although they often appear as small, dark brown spots, moles (nevi) vary in color and size. They can be raised or flat and can develop almost anywhere on your body.

Seborrheic keratoses. These tan, brown or black growths have a wart-like or waxy, pasted-on appearance.

Lentigo maligna. A type of skin cancer known as lentigo maligna melanoma can develop in areas of long-term sun exposure. Lentigo maligna starts as tan, brown or black lesions that slowly darken and enlarge. They tend to have an irregular border and uneven coloring, and they may be slightly raised.

If you're unhappy with the appearance of age spots, treatments are available to lighten or remove them. Since the pigment is located at the base of the epidermis — the topmost layer of skin — any treatments meant to lighten the age spots must penetrate this layer of skin.

Age spot treatments include:

Medications. Prescription bleaching creams (hydroquinone) used alone or with retinoids (tretinoin) and a mild steroid may gradually fade the spots over several months. Use of a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 30 is strongly advised if you use medication treatments. The treatments may result in temporary itching, redness, burning or dryness.

Laser and intense pulsed light therapy. Laser and intense pulsed light therapies destroy melanin-producing cells (melanocytes) without damaging the skin's surface. Treatments with a laser or intense pulsed light typically require several sessions. After treatment, age spots fade gradually over several weeks or months. Laser therapy has few side effects, but it may result in slight discoloration of the skin. Sun protection is also necessary after laser or intense pulsed light therapy.

Freezing (cryotherapy). This procedure involves applying liquid nitrogen or another freezing agent to the age spots to destroy the extra pigment. As the area heals, the skin appears lighter. Freezing is typically used on a single age spot or a small grouping of age spots. The treatment may temporarily irritate the skin and poses a slight risk of permanent scarring or discoloration.

Dermabrasion. This procedure consists of sanding down (planing) the surface layer of your skin with a rapidly rotating brush. This procedure removes the skin surface, and a new layer of skin grows in its place. Temporary redness and scab formation can result from this treatment.

Chemical peel. A chemical peel involves applying an acid, which burns the outer layer of your skin, to the age spots. As your skin peels, new skin forms to take its place. Several treatments may be necessary before you notice any results. Sun protection is strongly advised following this treatment. Temporary irritation is likely, and there's a slight risk of discoloration.

Because age spot treatments are considered cosmetic, your insurance may not pay for them. And because the procedures can have side effects, discuss your options carefully with your dermatologist. Also, make sure your dermatologist is specially trained and experienced in the technique you're considering.

Many fade creams and lotions for lightening age spots are available in department stores, in drugstores and on the Internet. These may improve the appearance of age spots, depending on how dark the spots are and how often you apply the cream. Regular use over several weeks or months may be necessary to produce noticeable results.

If you opt for an over-the-counter (nonprescription) fade cream, choose one that contains hydroquinone, glycolic acid or kojic acid. Note that some products, especially those that contain hydroquinone, may cause skin irritation.

To help avoid age spots, follow these tips for limiting your sun exposure:

Avoid the sun between 10 a.m. and 3 p.m. Because the sun's rays are most intense during this time, try to schedule outdoor activities for other times of the day.

Use sunscreen. Fifteen to 30 minutes before going outdoors, apply a broad-spectrum sunscreen that provides protection from both UVA and UVB light. Use a sunscreen with a sun-protection factor (SPF) of at least 30. Apply sunscreen generously, and reapply every two hours — or more often if you're swimming or perspiring.

Cover up. For protection from the sun, wear a broad-brimmed hat, which provides more protection than does a baseball cap or golf visor, and tightly woven clothing that covers your arms and legs. You might also consider wearing clothing designed to provide sun protection. An ultraviolet protection factor (UPF) of 40 to 50 provides the best protection.

Is microdermabrasion the right choice for you? American Academy of Dermatology. http://www.aad.org/dermatology-a-to-z/diseases-and-treatments/m---p/microdermabrasion/is-it-right-for-you#allpages. Accessed Nov. 24, 2013.

Reprint Permissions

A single copy of these materials may be reprinted for noncommercial personal use only. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research.